Circulating device for boiling apparatus or coppers.



AP UCATION HLED NOV 21 W32.

Patented Apr. 1%, 1916.

Witnesses- .lttorney.

UNITED STATES PATENT OFFICE.

AUGUSTE Bravo, ETR'EPAGNY, FRANCE, AssIGNoR. To socraTi'i ANONYME DES ETABLISSEMENTS ALFRED ,MAGUIN, or .CHARMES, NEAR LA FERE, FRANCE.

' omomarmo Device FOR BOILING APPARATUS on corrnas.

Specification of Letters Patent.

Patented Apr. 18, 1916.

Application filed November 21, 1912. Serial No. 732,739.

' provide a circulating device intended to impart suitable movement to the substance which is being boiled during its treatment in boiling coppers (or sugar boilers) in the manufacture of sugar; this circulating device is distinguished from devices already known for this purpose, and which comprise a. mixer provided in the interior of the vessel by the fact that it transmits motion at the exterior of the boiling apparatus.

The circulating device which is the object of the invention further of interest owing to the application of it to boiling apparatus, lyre shaped sugar boilers, and sugar boilers constructed with tubular members.

The accompanying drawing shows, in elc ration partly in section, constructional form of the device.

As will be seen in the drawing, the circulating device is constituted essentially by a vertical tube 1 of cast iron or any other sult able material provided at the side of the calender of the boiling apparatus; the tube 1 being closed at its upper and and com municating at its lower portion at one or two points with the bottom part 3 of sugar boiler. Further xii .uhe l co-rumunicates with the calender by means of a certain number of pipes 4 in the interior of the tube 1, rotates a shaft 5 provided with helical blades (5, 6 situated between two of the communicating pipes 4 as shown in the drawing. The pipes 4 are arranged in such a manner as to correspond with the interior arrangement of the heating surface and with the different stages of the boiling oper ation; granulation, feeding rich syrups and feeding syrup-water.

The screw rotates "at a suitable speed (generally 40 revolutions per minute) movement being transmitted to it by any suitable arrangement, for example, as shown in the drawing, by a worm 7 and helicoidal gear-wheel 8; the worm may be driven by a belt or by an electric motor.

The operation of the circulating device is as follows: As soon as the boiling mass reaches the first communication pipe, the circulating device is put in operation. It Wlll easily be seen that the mass which is moved downward by the first screw toward the bottom of the sugar boiler causes an energetic stirring in the latter. From this results a more rapid and more complete actionon the mother-liquor as regards sugar crystals; in other words, the crystals form better and increase more quickly than in similar apparatus as known up to the present time. In proportion to its rise in the apparatus, the boiling mass reaches the level ofthc second and then of the third communicating pipe; it is then acted upon by the screws 6 and successive screws of the circulating device which discharge it downward. Movement consequently is set up right through the apparatus; the mixture is thus perfect and crystallization very active owing to the movement imparted to the boiled mass which agitatos the crystals formed at the middle of the mother-liquor.

In order to avoid loss of heat, the circulating device may be surrounded by a heat retaining jacket; or a double steam jacket may also be provided for the same purpose.

The pipes 4: may, as in the drawing, communicate freely with the interior of the sugar boiler or be provided with closing devices, which allow, if necessary, of shutting off the circulating device from the boiling apparatus. X

Instead of a single circulating device two or a greater number may be provided at different points in the circumference of the boiling apparatus, when the diameter or arrangement of the latter requires it in order to obtain energetic stirring in the interior of the boiling mass.

It is to be observed that the boiling point of the liquid depends on the density of the concentrate. The higher the density the greater the temperature necessary to eflect evaporation. This will necessarily affect the heat etliciency, the necessary temperature of the heating medium, the heat leakage, and the heat conduction. Hence it is essential to keep the denser concentrates separate from the lighter ones and only use the latter for stirring up the mother liquor to modify the quality of the crystallization. This latter result is obtained by means of the regulating valves. It will be seen that the valves 9 can be used to control the circulation in various ways.

What I claim as my invention and desire to secure by Letters Patent is l. The combination with a boiling apparatus or boiler for sugar and the like, of a single circulating device comprising a single tube communicating with the boiler, pipes leading from the tube into the boiler at different levels and a communication to the bottom of the boiler.

9, The combination with a boiling apparatus or boiler for sugar and the like, of a circulating device comprising a tube mount ed vertically on the outside of the boiler,

.pipes leading laterally from said tube and communicating with'the boiler at different levels, a shaft within said tube and having blades mounted at intervals on it adapted to convey the contents of the tube downward, each blade being situated between a pair of said lateral pipes, and means for driving said shaft.

3. The combination with a boiling apparatus or boiler for sugar and the like, of a circulating device comprising a tube mounted .vertically on the outside of the boiler, pipes leading laterally from said tube and communicating with the boiler at different levels, a shaft within said tube and having blades mounted at intervals on it adapted to convey the contents of the tube downward each blade being situated between a pair oii said lateral pipes, means for driving said shaft and means for regulating the flow of I boiling material through any of said pipes.

4. The combination with a boiling apparatus or boiler for sugar and the like, of a circulating device, comprising a tube communicating with the boiler, pipes leading from the tube to the boiler, said tube con-' taining a shaft carrying a number of conveyer blades each blade being situated between a pair of the said pipes, means for driving said shaft and means for regulating the flow of boiling material through any of said pipes.

. 5. The combination with a boiling apparatus or boiler for sugar and the'like, of a circulating device comprising a series of tubes mounted vertically on the outside of the boiler at different points in its circumference, pipes leading laterally from said tubes and communicating with the boilerat difierent levels, a shaft within said tubes and having blades mounted at intervals on it adapted to convey the contents of the tube downward, each blade being situated between a pair of said lateral pipes, and means for driving said shaft.

6. The combination with a boiling apparatus or boi-lerfor sugar and the like, of a circulating device comprising a single tube communicating with the boiler, pipes leading from the tube into the boiler at difi'erent levels, and a communication to the bottom of the. boiler, and a circulating means in said tube.

7. The combination with a boiling apparatus or boiler for sugar and the like, of a circulating device comprising a single tube communicating with the boiler, pipes leading from the tube into the boiler at different levels and a communication to the bottom of the boiler, a circulating means in said tube, and valve controls for the pipes.

8. The combination with a boiling apparatus or boiler for sugar and the like, of a circulating device comprising a single tube mounted on the outside of the boiler, pipes leading from said tube and communicating with the boiler at different levels and a communication to the bottom of the boiler, a shaft within said tube, and having blades mounted at intervals on it adapted to convey the contents of the tube downward, each Hanson C. Coxn, MIGUEL ZEROLO.

blade being situated between a pair of said 

